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Ma Y, Huang X, Du H, Yang J, Guo F, Wu F. Impacts, causes and biofortification strategy of rice selenium deficiency based on publication collection. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169619. [PMID: 38157912 DOI: 10.1016/j.scitotenv.2023.169619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 12/21/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
Selenium (Se) deficiency in rice will result in a Se hidden hunger threat to the general public's human health, particularly in areas where rice consumption is high. Nevertheless, the impact scope and coping strategies have not been given sufficient focus on a worldwide scale. In order to evaluate the impacts, causes and biofortification strategies of Se-deficient rice, this study collected data from the publications on three themes: market survey, field sampling and controlled experiments. According to the market survey, global rice Se concentrations were 0.079 mg/kg on mean and 0.062 mg/kg on median. East Asia has a human Se intake gap due to the region's high rice consumption and the lowest rice Se concentration in markets globally. Total Se concentrations in East Asian paddy soils were found to be adequate based on the field sampling. However, over 70 % of East Asian paddy fields were inadequate to yield rice that met the global mean for rice Se concentration. The Se-deficient rice was probably caused by widespread low Se bioavailability in East Asian paddy fields. There were two important factors influencing rice Se enrichment including root Se uptake and iron oxide in soils. Concentrating on these processes is beneficial to rice Se biofortification. Since Se is adequate in the paddy soils of East Asia. Rather of adding Se exogenously, activating the native Se in paddy soil is probably a more appropriate strategy for rice Se biofortification in East Asia. Meta-analysis revealed water management had the greatest impact on rice Se biofortification. The risks and solutions for rice Se deficiency were discussed in our farmland-to-table survey, which will be a valuable information in addressing the global challenge of Se hidden hunger. This study also provided new perspectives and their justifications, critically analyzing both present and future strategies to address Se hidden hunger.
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Affiliation(s)
- Yuanzhe Ma
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xintian Huang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Huini Du
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jing Yang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fuxing Guo
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fuyong Wu
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling 712100, Shaanxi, PR China.
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Wang L, Luo P, Guo X, Zhang M, Li H, Liu F, Wu J. Leaching of soil legacy nitrogen in intact soil columns and significance of soil macropore structure. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167546. [PMID: 37802354 DOI: 10.1016/j.scitotenv.2023.167546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/18/2023] [Accepted: 09/30/2023] [Indexed: 10/10/2023]
Abstract
Excessive application of chemical fertilizers accumulates nitrogen in soil (soil legacy nitrogen), and its release has a long-term impact on environmental quality. The information regarding leaching of soil legacy nitrogen and role of soil pore structure is scarce. Fifteen undisturbed soil cores with a depth of ~200 mm were collected from five paddy fields in a subtropical area of China, and soil pore structure was characterized with X-ray computed tomography. The batch leaching column experiments were conducted to investigate the nitrogen leaching from the soil cores. In the leachate, inorganic nitrogen (NO3--N and NH4+-N) accounted for 73-85 % of total dissolved nitrogen (TDN), which showed small variations among the five sampling sites. The NO3--N, NH4+-N and TDN concentrations in the leachate over the number of leaching times could be well fitted with the Gaussian, exponential or linear models, suggesting that different nitrogen forms showed variable leaching dynamics. NO3--N and TDN leaching losses continued to increase with the number of leaching times, whereas NH4+-N leaching from the soil had a threshold value. Combination of changes in soil nitrogen content after leaching, the lagging effect of soil legacy nitrogen may be partly attributed to the continuous transformation of NH4+-N and organic nitrogen into NO3--N in the soils. Besides the nitrogen content in the soil, the most important factor of soil pore structure controlling NO3--N and TDN leaching loss was the fractal dimension; NH4+-N was mainly controlled by connectivity. The present study highlighted the importance of soil pore structure and nitrogen format transformation in the leaching of soil legacy nitrogen.
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Affiliation(s)
- Liufang Wang
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pei Luo
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China.
| | - Xiaobin Guo
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China
| | - Miaomiao Zhang
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China
| | - Hongfang Li
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China
| | - Feng Liu
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China
| | - Jinshui Wu
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Han H, Chen T, Liu C, Zhang F, Sun Y, Bai Y, Meng J, Chi D, Chen W. Effects of acid modified biochar on potassium uptake, leaching and balance in an alternate wetting and drying paddy ecosystem. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 900:166344. [PMID: 37597543 DOI: 10.1016/j.scitotenv.2023.166344] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/13/2023] [Accepted: 08/14/2023] [Indexed: 08/21/2023]
Abstract
Straw biochar amended soils reduce fertilizer losses and alleviate soil K-exhaustion, while decrease grain yield due to its high pH. H2SO4-modified biochar has been studied as a means to enhance the advantages of biochar and address yield decrease. However, little information is available on its effects on aboveground K uptake, soil K fixation, K leaching, and utilization in paddy rice systems, especially under water stress. A 3-year field experiment was conducted with two irrigation regimes (continuously flooded irrigation, ICF and alternate wetting and drying irrigation, IAWD) as main plots and 0 (control), 20 t ha-1 biochar (B20), and 20 t ha-1 acid-modified biochar (B20A-M) as subplots. The results showed that IAWD significantly decreased water percolation by 9.26 %-14.74 % but increased K leaching by 10.84 %-15.66 %. Compared to B0, B20 and B20A-M significantly increased K leaching by 32.40 % and 30.42 % in 2019, while decreased it by 11.60 %-14.01 % in 2020 and 2021. Both B20 and B20A-M significantly improved aboveground K uptake by 3.45 %-6.71 % throughout the three years. B20 reduced grain yield in 2019 and increased it in 2020 and 2021, while B20A-M increased grain yield throughout the three years. Apparent K balance (AKB) from pre-transplanting to post-harvest over the three years suggested that IAWD significantly increased the risk of soil K depletion but B20 and B20A-M significantly increased AKB, thereby addressing the depletion of it. IAWDB20A-M have a comparable AKB with ICFB20A-M, but had up to 18.3 % and 21.61 % higher AKB than IAWDB20 and ICFB20. Therefore, the use of H2SO4 modified biochar could produce higher grain yield with lower K leaching for addition in IAWD paddy systems, which is beneficial to mitigate soil K depletion and ensure a sustainable agricultural production.
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Affiliation(s)
- Hongwei Han
- College of Water Conservancy, Shenyang Agricultural University, Shenyang 110866, China
| | - Taotao Chen
- College of Water Conservancy, Shenyang Agricultural University, Shenyang 110866, China; National Biochar Institute, Shenyang Agricultural University, Shenyang 110866, China; Key Laboratory of Biochar and Soil Improvement, Ministry of Agriculture and Rural Affairs, Shenyang 110866, China.
| | - Chang Liu
- College of Water Conservancy, Shenyang Agricultural University, Shenyang 110866, China
| | - Feng Zhang
- College of Water Conservancy, Shenyang Agricultural University, Shenyang 110866, China
| | - Yidi Sun
- College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Yikui Bai
- College of Water Conservancy, Shenyang Agricultural University, Shenyang 110866, China
| | - Jun Meng
- National Biochar Institute, Shenyang Agricultural University, Shenyang 110866, China; Key Laboratory of Biochar and Soil Improvement, Ministry of Agriculture and Rural Affairs, Shenyang 110866, China.
| | - Daocai Chi
- College of Water Conservancy, Shenyang Agricultural University, Shenyang 110866, China
| | - Wenfu Chen
- National Biochar Institute, Shenyang Agricultural University, Shenyang 110866, China; Key Laboratory of Biochar and Soil Improvement, Ministry of Agriculture and Rural Affairs, Shenyang 110866, China
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Hu J, Bettembourg M, Moreno S, Zhang A, Schnürer A, Sun C, Sundström J, Jin Y. Characterisation of a low methane emission rice cultivar suitable for cultivation in high latitude light and temperature conditions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:92950-92962. [PMID: 37501024 PMCID: PMC10447601 DOI: 10.1007/s11356-023-28985-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 07/21/2023] [Indexed: 07/29/2023]
Abstract
Rice cultivation on paddy soil is commonly associated with emissions of methane, a greenhouse gas, but rice varieties may differ in their actual level of emissions. This study analysed methane emissions associated with 22 distinct rice genotypes, using gas chromatography, and identified the cultivar Heijing 5 from northern China as a potential low-methane rice variety. To confirm this and to examine whether Heijing 5 can perform similarly at higher latitudes, Heijing 5 was cultivated in field trials in China (lat. 32° N) and Sweden (lat. 59° N) where (i) methane emissions were measured, (ii) methanogen abundance in the rhizosphere was determined using quantitative PCR, and (iii) the concentrations of nutrients in water and of heavy metals in rice grain and paddy soil were analysed. The results demonstrated that the low-methane rice cultivar Heijing 5 can successfully complete an entire growth period at high-latitude locations such as central Sweden. Massively parallel sequencing of mRNAs identified candidate genes involved in day length and cold acclimatisation. Cultivation of Heijing 5 in central Sweden was also associated with relatively low heavy metal accumulation in rice grains and lowered nutrient losses to neighbouring water bodies.
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Affiliation(s)
- Jia Hu
- Department of Plant Biology, Sweden University of Agricultural Science, The Linnean Centre for Plant Biology, Box 7080, SE-75007, Uppsala, Sweden
| | - Mathilde Bettembourg
- Department of Plant Biology, Sweden University of Agricultural Science, The Linnean Centre for Plant Biology, Box 7080, SE-75007, Uppsala, Sweden
| | - Silvana Moreno
- Department of Plant Biology, Sweden University of Agricultural Science, The Linnean Centre for Plant Biology, Box 7080, SE-75007, Uppsala, Sweden
| | - Ai Zhang
- Department of Plant Biology, Sweden University of Agricultural Science, The Linnean Centre for Plant Biology, Box 7080, SE-75007, Uppsala, Sweden
| | - Anna Schnürer
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, SE-750 07, Uppsala, Sweden
| | - Chuanxin Sun
- Department of Plant Biology, Sweden University of Agricultural Science, The Linnean Centre for Plant Biology, Box 7080, SE-75007, Uppsala, Sweden
| | - Jens Sundström
- Department of Plant Biology, Sweden University of Agricultural Science, The Linnean Centre for Plant Biology, Box 7080, SE-75007, Uppsala, Sweden
| | - Yunkai Jin
- Department of Plant Biology, Sweden University of Agricultural Science, The Linnean Centre for Plant Biology, Box 7080, SE-75007, Uppsala, Sweden.
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Qi D, Zhu J, Wang X. Nitrogen loss via runoff and leaching from paddy fields with the proportion of controlled-release urea and conventional urea rates under alternate wetting and drying irrigation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:61741-61752. [PMID: 36934189 DOI: 10.1007/s11356-023-26480-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 03/12/2023] [Indexed: 05/10/2023]
Abstract
Alternate wetting and drying irrigation (AWD) can reduce non-point source pollution from paddy fields by mitigating field water depth. However, the influence of compounding modes of polymer-coated urea (PCU) and conventional urea (CU) on nitrogen (N) loss via runoff and leaching from paddy fields under AWD conditions remains unclear. To address this question, in this study, a 2-year field experiment was set up with three N management treatments: (a) 100% CU (N1), (b) 60% PCU + 40% CU (N2), and (c) 100% PCU (N3), at an equivalent N rate of 240 kg ha-1 that was applied to traditional continuously flooded (CI) and AWD systems. The results of this experiment showed a high-risk period of N loss from the paddy fields within 7 d after basal fertilization and 5 days after tillering fertilization. AWD reduced irrigation frequencies by 3.5 times and total input of irrigation water by 38.1%, increasing water utilization from precipitation by 44.4% than CI and reducing the volume of runoff by 46.1% and leaching water by 22.1%. This reduced the total N (TN) loss through runoff and leaching under AWD. In the N2 and N3 treatment groups, N concentration in floodwater decreased from 33.8 to 24.9%, TN loss via runoff decreased by 35.3 to 25.0%, and leaching decreased by 41.7 to 30.3% from the paddy field compared to N1. With the same N mode, AWD showed a higher N uptake (from jointing to maturity stage) and rice yield compared to CI. Besides, N2 and N3 had higher N uptake compared to N1 under the two irrigation regimes. Moreover, the AWDN3 and AWDN2 treatments resulted in the lowest and second-lowest loss of TN via runoff (2.21 to 2.66 kg ha-1) and leaching (8.14 and 10.21 kg ha-1), respectively, from the paddy fields and had the relatively high N uptake in rice in the maturity stage. Remarkably, compared with N3, N2 had a comparable grain yield under CI; however, it showed a higher yield under AWD, suggesting that there is a positive interaction in the rice yield between the AWD and compounding N (PCU + CU) fertilization practice. Thus, AWD coupled with N2 could be recommended as a useful approach to reduce N loss via runoff and leaching from paddy fields, which could increase the grain yield of middle-season rice.
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Affiliation(s)
- Dongliang Qi
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China.
- Engineering Research Center of Ecology and Agriculture Use of Wetland, Ministry of Education, Yangtze University, Jingzhou, 434025, Hubei, China.
| | - Jianqiang Zhu
- Engineering Research Center of Ecology and Agriculture Use of Wetland, Ministry of Education, Yangtze University, Jingzhou, 434025, Hubei, China
| | - Xiugui Wang
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China
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Yan J, Ren T, Wang K, Ye T, Song Y, Cong R, Li X, Lu Z, Lu J. Optimizing phosphate fertilizer input to reduce phosphorus loss in rice-oilseed rape rotation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:31533-31545. [PMID: 36449245 DOI: 10.1007/s11356-022-24133-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 11/05/2022] [Indexed: 06/17/2023]
Abstract
Identifying the major sources and critical periods of P loss from agricultural fields provides important guidance for reducing P loss. A rice-oilseed rape rotation with no P fertilization (NP, control), medium P fertilization (MP, 90 kg P2O5 ha-1 season-1), and high P fertilization (HP, 180 kg P2O5 ha-1 season-1) was conducted from 2019 to 2021 in the middle Yangtze River Basin. Runoff and leaching P losses were measured simultaneously using runoff event monitoring and a percolation device. Applying P fertilizer increased the P concentration in the field ponding water and percolation water of the rice-oilseed rape rotation. During the rice growing season, total P (TP), dissolved P (DP), and particulate P (PP) concentrations in the field ponding water and percolation water peaked 1 day after P was applied, and then decreased rapidly. After 10 days of fertilization, P concentration in the field ponding water of the MP treatment decreased to a minimum and stabilized, while the HP treatment extended this period to 20 days. The highest P concentration in percolation water was observed at the first sampling during the oilseed rape season, and then it continued to decrease. Inputting P fertilizer increased P loss by 55.0-109.9% compared to the NP treatment, with annual P losses of 0.89-1.10 kg P ha-1, of which runoff loss accounted for 61.7-62.9%. Fertilization and precipitation resulted in varied P loss within and between seasons. Runoff from heavy precipitation during the rice season was the main source of P loss, while PP accounted for 54.7-77.6% of runoff P loss. The strong utilization of soil P by rice resulted in a lower demand for exogenous P fertilizer than oilseed rape. Excessive P input increased the soil P surplus and vertical migration. Therefore, reducing rice season P fertilizer inputs to achieve annual P balance in rice-oilseed rape rotation can effectively reduce soil P surplus and loss while ensuring crop P demand, and the initial 10 d after fertilization in the rice season was a critical period for reducing P runoff loss.
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Affiliation(s)
- Jinyao Yan
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Tao Ren
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Kunkun Wang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Tinghong Ye
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Yi Song
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Rihuan Cong
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Xiaokun Li
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Zhifeng Lu
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China
| | - Jianwei Lu
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China.
- College of Resources and Environment / Microelement Research Center, Huazhong Agricultural University, Shizishan Street 1, Wuhan, 430070, China.
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Li Q, Qiu J, Liang Y, Lan G. Soil bacterial community changes along elevation gradients in karst graben basin of Yunnan-Kweichow Plateau. Front Microbiol 2022; 13:1054667. [PMID: 36620048 PMCID: PMC9813600 DOI: 10.3389/fmicb.2022.1054667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022] Open
Abstract
Elevation gradients could provide natural experiments to examine geomorphological influences on biota ecology and evolution, however little is known about microbial community structures with soil depths along altitudinal gradients in karst graben basin of Yunnan-Kweichow Plateau. Here, bulk soil in A layer (0 ~ 10 cm) and B layer (10 ~ 20 cm) from two transect Mounts were analyzed by using high-throughput sequencing coupled with physicochemical analysis. It was found that the top five phyla in A layer were Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, and Verrucomicrobia, and the top five phyla in B layer were Proteobacteria, Acidobacteria, Actinobacteria, Verrucomicrobia, and Chloroflexi in a near-neutral environment. Edaphic parameters were different in two layers along altitudinal gradients. Besides that, soil microbial community compositions varied along altitudinal gradient, and soil organic carbon (SOC) and total nitrogen (TN) increased monotonically with increasing elevation. It was further observed that Shannon indexes with increasing altitudes in two transect Mounts decreased monotonically with significant difference (p = 0.001), however beta diversity followed U-trend with significant difference (p = 0.001). The low proportions of unique operational taxonomic units (OTUs) appeared at high altitude areas which impact the widely accepted elevation Rapoport's rules. The dominant Bradyrhizobium (alphaproteobacterial OTU 1) identified at high altitudes in two layers constitutes the important group of free-living diazotrophs and could bring fixed N into soils, which simultaneously enhances SOC and TN accumulation at high altitudes (p < 0.01). Due to different responses of bacterial community to environmental changes varying with soil depths, altitudinal gradients exerted negative effects on soil bacterial communities via soil physical properties and positive effects on soil bacterial diversities via soil chemical properties in A layer, however the results in B layer were opposite. Overall, our study is the first attempt to bring a deeper understanding of soil microbial structure patterns along altitudinal gradients at karst graben basin areas.
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Affiliation(s)
- Qiang Li
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China,*Correspondence: Qiang Li, ✉
| | - Jiangmei Qiu
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China
| | - Yueming Liang
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China
| | - Gaoyong Lan
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China
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